Techniques for transmitting moving image data are susceptible of broad application. For example, the techniques have been applied in next-generation cellular phones, and it is possible to send/receive moving images among TV cellular phones while producing moving image data during communications.
In the conventional techniques, however, there has been a problem that media data for moving images created by other devices cannot be reproduced by the function of TV cellular phones realized by H.324 protocol. Consequently, it is necessary to implement a memory in the cellular phone for editing software and media files to reproduce the media data.
Besides, as a technique similar in field to the present invention, there is found “intercommunication system between different TV phones” in Japanese Patent Applications laid open No. HEI8-46723. The system was proposed for the purpose of enabling intercommunication among different types of TV phones, which had not been achievable because of diversity in protocols. In the intercommunication system, n(n−1) pieces of protocol converters are prepared for n types of TV phones, and the converters are selectively used according to DTMF (Dial Tone Multi Frequency) instructions to set up connection.
In the system, however, it is necessary to provide n(n−1) pieces of protocol converters for n types of TV phones. In other words, numbers of protocol converters are required depending on the number of TV phone types. In addition, the system does not respond flexibly to a switch in converters.